This invention relates to a method and apparatus for jetting ink, and more particularly to a method and apparatus by which ink is supplied from a reservoir to one or more ink jets.
Ink jet apparatus typically employ an ink jet chamber having an orifice for ejecting droplets of ink which is supplied by an ink handling system. Ink handling systems frequently include bubble trap chambers which are adapted to prevent bubbles of air from reaching the ink jet chamber and clogging the relatively small passages leading to the chamber or causing compliance so as to reduce the effect of the "jetting" pressure pulse which would thereby interfere with the proper operation of the ink jet. Ink handling systems may also include level sensors for sensing the amount of ink in an ink supply or reservoir associated with the system. Both bubble trap chambers and level sensing typically require a particular orientation to function properly. In other words, if an ink jet apparatus employs the bubble trap chamber and/or a level sensor is inclined or inverted, the bubble trap chamber and/or the level sensing mechanism may not function properly. Ink handling systems also typically assure a predetermined and proper hydrostatic head at the ink jet chamber.
It will therefore be appreciated that it is particularly important that the ink path immediately preceding the ink jet chamber have predetermined characteristics. It is not therefore possible to simply couple an ink jet chamber to a remote ink handling system by means, for example, of a tubular connection and still achieve reliable and high performance operation of the ink jet.